Accessible video comes down to three parts
Making a video accessible means covering both people who can't hear it and people who can't see it. More than 1 in 4 adults (28.7%) in the United States have some type of disability, per the CDC, and about 15% of American adults – 37.5 million people – report some trouble hearing, per the NIDCD. Video that only works with sound on shuts a large audience out.
Three building blocks do the work: captions, a transcript, and audio description. Captions put the spoken audio and relevant sounds into text. A transcript is a full text alternative to the whole clip. Audio description narrates the important visuals for someone who can't see the screen. Each maps to a specific WCAG success criterion, so you can check them off one at a time.
None of this needs specialist software. Start from an accurate transcript of the audio – you can turn the file into a transcript first – then reuse that text as both the media alternative and the script you time into captions. Get the transcript right and two of the three fall out of it.
Captions carry the audio: WCAG 1.2.2, Level A
Captions are the baseline. Under WCAG 2.1 Success Criterion 1.2.2, a Level A requirement, captions must be provided for all prerecorded audio in synchronized media. That's the lowest conformance rung, so any video with speech or meaningful sound needs them to clear even the minimum bar.
Captions differ from a plain transcript in one way that matters: they're synchronized, appearing in time with the audio, and they carry speaker turns and relevant non-speech sounds. The practical path is to export a caption file from your transcript – an SRT for social platforms and most players or a WebVTT track for HTML5 video on your own site – then check the timing against the clip.
There's one narrow exception. SC 1.2.2 doesn't require captions when the video is itself a media alternative to text already on the page and is clearly labeled as such. For ordinary video content, that exception won't apply, so plan on captions. For the mechanics of building and timing the file, see how to add subtitles to a video.
A transcript is the media alternative: WCAG 1.2.3, Level A
A full text transcript satisfies its own Level A criterion. WCAG 2.1 Success Criterion 1.2.3 is met by either audio description or a media alternative – a text document carrying all the information in the video, both what's said and what's shown. A complete transcript is that media alternative.
To count as the media alternative, the transcript has to include more than dialogue. It needs the visual information too: who appears, what they do, on-screen text, and anything a viewer would otherwise get only by watching. Write it so someone could follow the whole video by reading alone. Label it clearly and place it near the player so it's easy to find.
This is where the build-once approach pays off. The same transcript that serves as your 1.2.3 media alternative is also the script you time into captions for 1.2.2. Producing an accurate transcript by hand is slow – up to six hours of work per hour of audio – so an automatic first pass you then correct saves the bulk of that time.
Audio description is the Level AA step people skip
Audio description is the requirement most people miss. To reach Level AA, WCAG 2.1 Success Criterion 1.2.5 says authors must provide an audio description of the prerecorded video. A text transcript used to meet 1.2.3 at Level A doesn't discharge this: at AA, audio description is a separate, additional requirement.
Audio description is a narration track that describes the important visual details a soundtrack alone leaves out: a chart on screen, a facial expression, on-screen text, a demonstrated action. It fits into the natural pauses between dialogue. If your video carries meaning in its visuals, this is the piece that delivers it.
The Level distinction is the trap. You can add captions and a transcript, satisfy 1.2.2 and 1.2.3, and still fall short of AA because 1.2.5 is unmet. Since ADA Title II and Section 508 both point at Level AA, budget for audio description from the start rather than treating it as optional polish.
Which ADA standard applies to your video?
The ADA names no technical standard for video, but the rules that reference one point to WCAG. DOJ's 2024 ADA Title II final rule adopts WCAG 2.1 Level AA as the technical standard for state and local governments' web content and mobile apps. Federal agencies fall under Section 508 instead.
For Title II, deadlines depend on size. Public entities with a total population of 50,000 or more must conform by April 26, 2027. Entities under 50,000 and special district governments have until April 26, 2028, after the April 2026 Interim Final Rule extended both dates by a year. Section 508 covers federal electronic content and incorporates WCAG 2.0 Level A and AA, effective January 18, 2018.
Note the version gap: Title II references WCAG 2.1 while Section 508 still references 2.0. If both could touch your video, build to 2.1 AA to satisfy the higher bar. For private businesses under Title III, DOJ guidance says entities have flexibility in how they comply and treats WCAG as helpful guidance rather than a fixed rule. This is general information, not legal advice – confirm your obligations for your situation.
